fix: let a draft-only schedule, trigger or resource be deleted (#11010)

* fix: let a draft-only schedule, trigger or resource be deleted

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012SV5kjTis3AFtTx2nW2VRi

* fix: keep the legacy-draft write gate out of the draft-only delete

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012SV5kjTis3AFtTx2nW2VRi

* fix: don't gate a draft-only resource discard on the deployment rules

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012SV5kjTis3AFtTx2nW2VRi

* docs: condense the draft-only delete comments per the comment policy

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012SV5kjTis3AFtTx2nW2VRi

---------

Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>